To celebrate this almost-holiday (as well as what is unquestionably the best Bill Murray movie of all time), I want to share the easiest way you can boost response to an email-driven campaign — fundraising, advocacy, whatever. You can spend 30 minutes to increase revenue or actions driven by your very best-performing messages by 50-100%.

All you do is take a message that has gotten an above-average response from your email list, and then… send the exact same message again, to the same audience. Relive the experience, just like TV weatherman Phil Connors!

Just change the subject line, suppress people who have already completed the ask (or openers of the first send, if you want to be a bit more conservative), and voila!

Were you hoping for something subtler? More technically complicated? Maybe a social media angle?

Here’s the thing. You’re only getting, what, a 13% open rate on your first send? Maybe a little higher, maybe lower, but no matter who you are, most of the people you sent your high-performing appeal to didn’t even bother to read it.

But you know that the people who did open it liked it, right? Because a lot of them took action or donated. So a resend is just an easy way to get those 87%-ish people who ignored you the first time a chance to read your stunningly convincing message.

I believe this is what’s known as having your cake and eating it, too.

Second, make sure you suppress people who took action or donated the first time. There’s no quicker way to prove to supporters that you don’t care about them than by demanding they do something they literally just did.

Third, timing is everything. Don’t abuse this tactic, because if your supporters start seeing you resending the same content every other day, they’re going to tune you out pretty quickly. And think about the spacing of your resends. For an urgent message (say, a fundraising deadline or an imminent vote in Congress), you may want to do a second send just a few hours after the first message. For something with a bit of a longer tail, you can go a couple days to let stragglers from the first message come in before hitting launch on your second send.

So that’s it! You need a new subject line (luckily, you brainstormed at least five before sending the first message, right?), an updated audience, and a few minutes to clone your message. And when your boss asks how you’re getting so many more donations and actions, you have a simple answer: